Pump



c. E. NAGEL PUMP Filed: Ma :51, 1925 2 Sheets-Sheet 1 VENTOR CA 5 NAGEL.

ATTORNE s.

flan. 20. 1925; I 1,523,707

c. E. NAGEL PUMP File ay 31, 1925 2 Sheets-Sheet 2 INVENTOR CARL 5. NAGEL.

ATTORNE s.

such a spring UNITED STATES PATIENT OFFICE.

CARI/E. NAGEL. or OAKLAND, camromvm.

rnmr.

Application filed May 31,

-To all whom it may concern:

Be it known that I, CARL E. NAGEL, a citizen of the United States,residing at Oakland, county of Alameda, and State of California, haveinvented new and useful Improvements in lowing is a specification.

This invention relates to a pump and especially to that type whichdepends upon the viscosity of an oil or other fluid film for itsoperation.

Fuel pumps at present employed for the purpose of supplyingv fuel oilunder high pressure to the fuel. valve ornozzle of a Diesel engine,especially such engines as employ solid or mechanical injection areusually of the variable displacement type. I pumps require expensiveworkmanship on the fitting of the plungers, valves, etc., as thepressures-employed often exceed 4,000 pounds per square inch.[

In. the usual fuel system the pump de livery is not exactly timed tocoincide with the opening of the-fuel valves and various storage systemsare, therefore, required as, for instance, an air dome in which the en-T trapped air is highly compressed when thefuel pump delivers itscharge; this air being permitted to expand and force thefuel out of theline when the fuel valve lifts. Devices arealso necessary in fuelsystems of this character, such as spring loaded-plungers which operatein a cylinder to uncover a port in the side of the cylinder, therebyby-passing any "excess fuel delivered by the pump and returning it'tothe supply line;

' ing the building up of excess or dangerous l '1 and links andfthe-lostmotion due to wear.

pressures.

The governors employed on Diesel'engines are generally of thecentrifugal type and are usually connected with the part to be operatedby means of a number of links, levers,

etc. Such governors are generally sluggish in operation, and permitconsiderable speed. variations before they operate; this being due tothe friction encountered in the levers Theobject of the presentinventionis to generally-improve and simplify the construction an o eration ofpumps of the rotating t pe w ich-depend upon the viscosity of like fluidfor its operation; to character which will an 0i or provide a pump ofthis have a sufiicient capacity to serve as a Pump, of which the fol-Such loaded plunger also preventa fuel 1923. Serial No. 642,412.

valves, etc. Other objects will hereinafter appear.

One form which my invention may assume is exemplified in the followingdescription and illustrated in the accompanying drawings, in Which- Ysection of the pump.

Fig. 2 is a side elevation partly broken away, said figure also showingone-half of the pump cover removed. v

Fig. 3 is an enlarged detail plan view. of one of the shoes.

' Fig. 4 is a side elevation'of thesame.

Referring to the drawings in detail, and paticularly to Figs. 1 and2,'A'indicates in general a pump casing which in this instance isdivided into two sections such as lndlcated at 2 and 3; these sectionsbeing secured together'by means of bolts and nuts as indicated at 4 and,5. Formed between the two pump casing sections indicated at 2 and 3 isa; central chamber 6, and mounted in said chamber is a disk or rotor 7which is secured on a driving shaft 8, the shaft 8 being journaled as at9 in a bearing member 10 forming a portion of the casing section 3. Thecentral chamber 6 is circular in formation and its peripheral portion isenlarged on each side of the rotor 7 to form a pair of communicatingannular chambers 11 and 12. Disposed in the chamber 11 are a pluralityof shoes 13 and similarly disposed in the chamber 12 are .a plurality ofshoes 14; these shoes being interspaced as shown at 15, in Fig. 2, andbeing held in what may be termed frictional engagement with. theopposite faces of the rotor 7 by means of pins 16- These; pins aresupported by the re- F 'g. 1 is a central, vertical, longitudinal 70means of a coupling 26. 10,

pin is connected with a discharge pipe 23 by means of suitable couplingssuch as indi cated at 24; the pipes 23 being all connected with a commonmanifold not here shown.

The fuel oil to be pumped and discharged under pressure is deliveredfrom a suitable source through a pipe 25, which is connected with thecenter portion of the casing 2 by The oil thus entered is discharged bycentrifugal force against the shoes 13 and 14, which, due to theviscosity and the adhesive quality of the oil, is forced between theshoes 13 and 14 and the rotor in the form of a film, a portion of thisfilm being continuously discharged through ports 27 formed in therespective shoes which align with the ball and socket bearings 21 andthe discharge passages 22 and pipes 23.

It should be remembered that the pump forming the subject matter of thepresent application depends upon the viscosity of an oil or like fluidfilm for its operations; therefore, to clearly explain the principle ofoperation the following facts might be stated:

When one flat surface, for instance, the inner face of the shoe 13illustrated in Fig. 4, is-pressed directly against another flat surface,for instance, the side of the rotor 7, (see the same figure), and if itis assumed that the side of the rotor or flat surface is covered withoil, the oil film between thetwo surfaces will be squeezed out. On theother hand, if movement is imparted to one flat surface or, inotherwords, the rotor, the two faces when free to move with relation to eachother will assume an inclined position as illustrated in Fig. 4 andthereby become separated by a wedge-shaped film of oil. The filmthickness increases with the viscosity of the oil and the speed of therotor, but experience has shown that no low speed or high speed limitscan be reached. Furthermore, that the pressure on the film between theshoe and the rotor varies from nothing or zero at the edges of the shoesand reaches a maximum about centrally of the shoe or at a point inalignment with the discharge port 27. If it is desired to discharge oilunder high pressure, it is only necessary to increase the speed.Assuming that the viscosity of the oil remains constant and if it isdesired to discharge the oil under lower pressure, it is only necessaryto lower the speed.

T 0 further illustrate the operation we will first consider the actionwhen no oil is drawn off through the ports 27 and when the rotor isturning very slowly. In this case only a small amount of oil is carriedunder the shoes by the rotor and very little pressure is generated underthe shoes, it being furthermore found that there is only a slighttendency to force the oil out at the side edges of the shoe. If this isthe case the film of oil formed will, practically speaking, assume auniform thickness from end to end of the shoe.

.Ve will next consider an increase in speed. If this is the case theamount of oil carried by cohesion becomes greater and the leading edgeof the shoe is thereby slightly lifted and a wedge shaped film is formedas shown in Fig. 4. Tilting of the shoe with relation to it's stationarysupport causes pressure to be generated in the oil film and thispressure forces apart of the oil out under the side edges of the shoesand if we assume that the speed and pressure generated-are such thatone-fourth of the oil entering under the leading edge is squeezed out atthe sides, then the thickness of the film of oil under the trailing edgewill be three-quarters that of the film thickness under the enteringedge.

For each speed of rotation there is a certain inclination on the face ofthe shoe which differs from that of any other speed, and where the shoesaremot free to tilt on their ball and socket bearings, there would beonly one speed at which high pressure could be obtained for at thatspeed only would the relative thickness of the film of oil at theentering and trailing ends be properly. proportioned.

\Ve will next consider the action when the rotor is turning at a fixedspeed and oil is discharged through the ports 27; that is, we

will assume that the faces of the'shoes have assumed a position such asshown in Fig. 4, this figure showing an exaggerated wedge of oil. \Yhena small amount of oil is allowed to pass through the port 27 in thecenter of the shoe. this escape or discharge reduces the amount of oilescaping at the trailing end and as this is the case the trailing end ofthe shoe drops, thus raising the leading dege and thereby admitting anincreased amount of oil under the shoe.

lVith the operation continued a condition of equilibrium will be set upand the same oil pressure will be maintained when oil is drawn offthrough the central port 27 as exists for the same speed of rotationwith no oil passing out. Again, if the shoes were fixed or caused toassume a predetermined inclined or angular position, and oil is allowedto pass out, the pressure would drop, as there would not be enough oilleft under the shoe to maintain the pressure, but when the shoeispermitted to automatically tilt as here illustrated, the pressure willbe constantly maintained as the amountof oil escaping through the port27 is compensated for by automatically increasing the inclined positionof the shoes. It is for this reason that the pump is particularlyadapted to furnish fuel oil to a Diesel engine employing solid ormechanical injection. By employing a multiplicity of shoes with the disicharge pipes'23 connected to themego'z reel pipe which leads to the fuelvalves, and with the pump driven by the engine, it can beseen that, whenthe fuel valves are operated in'succession by the usual mechanism, fuelwill be delivered from the pump direct to the fuel valves and the fullpressure will be maintained as long as the fuel valve is open; that is,the fuel pressure will not drop during the opening period as is'thecasewhen the pressure is furnished by the' "expansion of the air n the airdome or some similar arrangement as previously referred \Vhen the fuelvalves {are closed the shoes automatically adjust --themselves to thiscondition and the oilpressure in the will thus remain the same as pipingsystem when the pump is. discharging oil, thus eliminating the necessityof safety or bypass valves and furthermore preventing building up ofexcessive or dangerouspressures in the piping system.- [While ajpressureof 4,000 pounds'is readily obtained; it should be understood thatthepressure may be increased or decreased eithe'r'by-adjust;

ing the position of the pins. so as tobring the-shoes into closercontact with thefsides of the rotor or by increasingthe speed of therotor or. decreasing the sameas the Pressures approxlmatmg case. may be.

as the experience and judgment of the manufacturer may dicate or varioususes may demand.

Having thus described my invention, what I claim and desire to secureby- Letters Patent is 1. In a pump of the character described,

a rotor, means for applying a film of oil to the surface thereof, meansfor placing said film under pressure, means optionally per-' mitting aportion of the oil in the film to continuously or intermittentlydischarge under pressure, and means for automatically maintaining apredetermined and constant .pressurewhether the discharge be continuousor intermittent.

2.- In a pump of the character described,

a rotor, means for applying a film of oil to the surface thereof, meansfor placing said film under pressure-,-f lmea ns optionally permitting aportion of the oil in the film to continuously or intermittentlydischarge un- ,der pressure, means for automatically main 14,000 poundsper square inch can be ob} tained, but such pressures are-not neces.

- siredl Experience. has shown "that the thicker films allow greaterproportions of Y oilto be withdrawn before the trailing-edge pressure istherefore encountered. The onlyv change in-pressure will becaused'byvariaof .the shoe is in dangerofcqntacting with the rotor. Itshould be understood-that the viscosity of the oil, practicallyspeaking,

remains constant and that thespeed of therotor varies. with enginespeed'ja's it ,isdriven thereby. As this is the casefit is only neces-'sary to adjust the individnal'fshoes'when thev sary and the supportingpins lfi' are there fore adjusted to produce a film which will give thequantity of oil. and pressure depump is installed as a specific or predetermined maintaine properly adjusted, .it can be seen'that a" pre--determined. pressure will be maintained; this being true whether thefuel valves are open or closed. If the fuel valves are open and the'fueloil is discharging,theq tilt of are closed, the tilt decreases andnolrise in tion in speed of the rotor.

I wish it understood that while certain features of the presentstructure are more pressure is usually employed and- When the shoes havebeen the shoes will increase, and if the fuel valves f -s1 pp'ort,' foreach shoe permittin taining a predetermined and constantpresa surewhetherthe discharge be continuous or intermittent, and'means forincreasing or decreasing-tthe pressure by increasing or decreasing thespeed of the rotor.

3.. Ina pump of' the-character described,

a-rotor, means for. applyin a film of oil to the surface ofthe rotor, ap urality. of shoes positioned adjacent the surface of the rotor andadaptedto form a plurality of wedge shaped oil films, and also adaptedto maintain said films under pressure, and means for increasing or.decreasing the pressure of of the rotor and to form a plurality of wedgeshaped oil films, and an adjustable an m-. crease ,or decrease in thespacing between the shoes and. the rotor.

5. In a pump of the'character described,

.a casing-,j chamber formed ,therein, a disk shaped rotor disposed insaid chamber, means for'rotatingthe rotor, a plurality of shoes disposedin the chamber adjacent one or less specifically illustrated,thatjvarious changes in form and proportion I may be resorted to withinthe scope of the appended claims. I Also, that the material's and.finish of the several parts employed may. be such face of the rotor,'means for maintaining "a predetermined spacing between each shoeandfthe rotor, and means permitting a slight tilting movement of eachshoe'with relation to the rotor.

6. In a pump of the character described,

a' casing,a chamber formed therein, a disk shaped rotor 'dlSPOSGd 1nvsaid chamber.

means for rotating the rotor, a plurality of shoes disposed in thechamber adjacent one face of the rotor, a ball and socket bearingforming a support for each shoe, and means permitting adjustment of eachball and socket bearing to increase or decrease the spacing between theshoes and the rotor. said ball and socket bearings also permitting atilting movement of each shoe with relation to the rotor.

7. In a pump of the character described, a casing, a chamber formedtherein, a disk shaped rotor disposed in said chamber, means forrotating the rotor, a plurality of shoes disposed in the chamberadjacent one face of the rotor, a ball and socket bearingforming asupport for each shoe, means permitting adjustment of each hall andsocket bearing to increase or decrease-the spacing between the shoes andthe rotor, said ball and socket bearings also permitting a tiltingmovement of each shoe with relation to the rotor, a discharge portformed ineach ball and socket bearing, and a discharge port formed ineach shoe in alignment therewith.

8. A pump of the character described comprising a casing having achamber formed therein, a shaft extending through one side of the casingand journaled therein, a disk secured on said shaft, bearing pinsextending through each side of the casing and entering the chamber, saidpins being adjustable on the longitudinal ,axis and each pin having acentral discharge port formed therein and extending longitudinallytherethrough, a plurality of shoes disposed in the chamber adjacent theopposite faces of the disk, each shoe having a discharge port formedtherein, a ball and socket bearing formed between each shoe and pin topermit a slight tilting movement of the shoes with relation to theopposite faces. of the disk, and means for delivering oil to the chamberin the pump casing.

9. In a pump of the character described, a smooth surfaced rotor, aplurality 'of shoes cooperating therewith, and means permittingadjustment'of the shoes to and away from the surface of the rotor.

10. In a pump of 'the character described, a smooth surfaced rotor, apluralityof shoes cooperating therewith, and means permitting a tiltingmovement of the shoes with relation to the rotor.

11. In a pump of the character described. a rotor, a plurality of shoescoing a support for each shoe, each shoe having a discharge port formedtherein, and a discharge pipe connected with each ball and socketbearing and communicating with the discharge ports in the shoes.

14. In a pump of the character described, a rotor, a plurality of shoescooperating therewith, a hall and socket bearing forming a support foreach shoe, each shoe having a discharge port formed therein, a dischargepipe connected with each ball and socket beariug and communicating withthe discharge ports in the shoes, means for delivering oil to a pointintern'iediate the shoes and the rotor. and means for adjusting theshoes with relation to the rotor toincrease or decrease the spacingbetween the shoes and the rotor.

15. In a pump of the character described, a rotor,'mcans for applying afilm of oil to the surface of the rotor, a. plurality of shoes pivotallysupported adjacent the surface of the rotor and adapted to form aplurality of wedge-shaped oil films, and also adapted to maintain saidfilms under pressure, and means permitting discharge of a portion of theoil in each film through the shoes.

CARL n. Naenn

